If you get eaten, it’s pretty safe  to assume that’s the end for you.… Except in the surprisingly frequent cases where you pop back out and go on living  your life like nothing ever happened.

Animals have an incredible number of  strategies to survive being eaten, from wiggling through a predator’s  gills to riding it out all the way through the digestive system and  miraculously living to tell the tale. Yes I am talking about butts!

With all of their death-defying maneuvers, these Shawshank-level escape artists  might make you lose your lunch. [intro music] Ok, ok, I know that not  everyone will agree with me and the experts that this first  example even counts as being eaten. But we’re starting with the earliest evacuations and building to the most unbelievable here and I think the predator had intent  to eat, and that’s what matters. It’s a battle of attrition between  catfish and water scavenger beetles.

A catfish captures its lunch: a delicious beetle. The next moment, the beetle  is back out in the water, swimming around right in  front of the catfish’s face. But the catfish isn’t deterred yet.

It snatches up the beetle again,  right into its hungry maw. And, just like before, the beetle  appears back in the open water, and definitely not in the catfish’s empty stomach. Researchers described these catfish as looking "as frustrated as a fish can look." And who could blame them?!

In one study, the beetles made  it out of the catfish’s mouth about 70% of the time! At some point, you just have to  say that beetle isn’t worth it! Now, we don’t know exactly how the  beetles have gotten so good at this, but the researchers have a few ideas.

The beetles might scramble  around the catfish mouth until they get an opening, or maybe they cling to the side of the mouth and irritate the catfish  into spitting them back out. Better out than in I always say! That was my Shrek impression...

But, whatever they’re doing in there, we know they need to be small to pull it off. Big beetles rarely survived. And that might be because the  catfish had an easier time manipulating those chonky boys in their mouth … to be gulped.

So for catfish with a taste for tiny beetles, let this serve as a lesson on the  importance of always chewing your food. But aquatic predators also  have a few more exit points. Like the gills!

When the ominously named  Dark Sleeper fish swallows a young Japanese eel, things start looking pretty bleak for the eel. But a little more than half the time, the eel manages an escape! First, a little eel tail  peeks out of the fish’s gills.

And I’d imagine that’s not  very comfortable for the fish because it starts rubbing against nearby surfaces  to get the rowdy would-be meal out of there. Now, I don’t know about you, but if I were escaping from inside a fish, my first thought would be “You’ve really gotten yourself  into a pickle now, Ceri.” Quickly followed by my second thought, which would be to exit head  first or at least facing forward. But these eels take the opposite approach.

And I guess we can’t knock them for it because about half of the time it works. Generally, when an eel is escaping  a predator out in the open, they’ll retract their head in response  to a threat and rapidly swim backwards. So when they’re escaping from inside the predator, it seems this tactic works just as well, slotting themselves into the gills  and letting them wriggle from there.

The eel’s approach seems well  suited for their long, thin bodies. Other, similar shaped elongate  catfish and deep sea eels have been said to escape from  sharks with this same method. My body, in comparison, is far too human to pull  off that kind of maneuver.

But being big comes with different advantages when you’re trying to escape. When a boa constrictor swallows an iguana, it probably thinks it has dinner taken care of. Surely after five minutes, the iguana is dead.

But in at least one such  encounter observed by scientists, the boa constrictor’s eyes might  have been too big for its stomach. At about 40% of the snake’s mass, the iguana was an exceptionally large meal. And after an alarming amount of time, the snake spat out the large iguana … who made a full recovery by the way.

The experts who described this in the  journal “The Herpetological Bulletin” think that certain adaptations  allowed the iguana to survive under those extreme circumstances. Like how reptiles can change their metabolic rate and thus their need for oxygen, which was probably not plentiful inside the snake. But being big isn’t the only  thing that can get you spat out.

Before we get to the next escape,  though, all science needs funding, even the science of not being eaten. So here’s a quick ad. This SciShow video is supported by DeleteMe, the subscription service that provides  set it and forget it peace of mind.

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And they’ll review yours too for  20% off DeleteMe consumer plans when you go to joindeleteme.com/SCISHOW and use promo code SCISHOW at checkout, or use the QR code on-screen. Some animals make it all the  way to their predator’s stomach before initiating their escape plan. You may have heard of the bombardier beetle.

They’re somewhat famous for blasting  toxic chemicals out their butt to dissuade predators. And on top of just being toxic, the chemicals are boiling hot, often  coming out at 100 degrees Celsius! So unsuspecting toads that  try to eat these beetles are in for the shock of a lifetime.

The beetles create their  dramatic effect a bit like the ol’ mixing mentos and  diet coke together trick. Rather than a single chemical  that can be fired at will, they mix two separate chambers of  chemicals together to oxidize them and create a boiling and explosive effect. And, luckily for the beetles, this reaction can happen  even from inside a predator.

You can hear the spray going off inside the toad! it's super freaky. Researchers studying this  defense prevented the beetles from releasing their toxic  chemicals, and sure enough, the beetles were eaten. … And stayed eaten. But without any tampering, up to 57%  of beetles were spat up by toads, even after 100 minutes.

If you were impressed by the iguana’s  longevity in a boa constrictor, that’s nothing compared to these beetles. It’s not the most dramatic  escape on our list, though. That belongs to the creatures who make it all the way  through the digestive system.

It’s time for butts! A lot of animals use this method of escape. First up are stick insects.

Birds are all too happy to  eat adult stick insects. And those guys don’t tend to escape. But their babies do!

Viable stick insect eggs have been observed  passing through Bulbul bird guts intact. They survive the bird’s digestive system and then hatch successfully  into healthy young insects. After, you know, ejecting out  the other end of the bird.

If you know what I mean… cloaca. Those eggs basically come  pre-packaged in their own escape pods. Stick insects have tough egg cases that are generally regarded as  a big factor in their success.

So the sturdiness of the eggs  probably contributes to them getting through bird digestive systems. Plus, the mothers are capable of parthenogenesis, so they don’t need to find another  insect to fertilize those eggs. But other animals can create a  sealed off escape pod for themselves.

Various species of snail can  retreat into their shells and drift through their  predator’s gut like a lazy river until they come out on the other end. Probably not as relaxing as the lazy  rivers you and I are familiar with, but it’s survivable...just a little poopier.. And as you’d expect, the shell is important here.

Like its overall integrity. One publication in the journal “Science” found that any crack or puncture  in the shell doomed a snail, which often got digested by a hungry fish. But if your shell stays intact, there’s an additional feature that  helps snails make the journey.

It’s called an operculum. Some snails have this thing  like a hinged door to the shell that they can close to seal everything up. By sealing themselves in and  slowing their metabolism, they can tolerate low-oxygen conditions long enough to make it through  the fish’s digestive system.

Even fish like the Spiny Sculpin  that are adapted to eat tough, hard prey like snails and crustaceans will poop out live snails that  took advantage of this feature. Other shellfish like limpets and hermit crabs that don’t have an operculum  are eaten and digested without too much trouble. Moral of the story: If you find  yourself on a treacherous journey, you’re going to want a properly sealed escape pod.

And for animals that don’t have an escape pod, speed needs to be on their side if  they’re going to make it all the way through someone else’s digestive system. One type of water beetle can crawl through  a frog’s GI tract in just six minutes! Okay, so that’s the record.

Most of them take a bit longer than that. But one study found that the  beetles who make it through alive do it within around 4 hours. And, I know, that’s still too long if  you need to do things like breathe.

But researchers think that being  aquatic helps them out there. They’re adapted to keep a small pocket  of air with them when submerged, which likely helps them in the  poorly oxygenated frog stomach. As well as having a tough  exoskeleton and a streamlined body.

So these beetles can get through the frog  guts fast and stay alive the whole time, with about a 90% survival  rate after getting eaten! Incredibly, for many animals, being swallowed isn’t  necessarily a death sentence. But it doesn’t sound all that fun either. … Unless you really want to get  back at a catfish for something.

So if you’re an animal with a predator after you, maybe try to avoid being eaten in the first place. [ outro music ]